Knee Surg, Sports Traumatol, Arthroscopy (1995) 3:187-191 lKnee Surgery [Sports Traumatology [ Arthroscopy �9 Springer-Verlag 1995

Anterior cruciate ligament reconstruction combined with valgus tibial osteotomy (combined procedure)

A. Boss ~, G. Stutz j, C. O u r s i n 2, A. G/ i chter 3

L Department of Orthopaedic and Trauma Surgery, University Hospital Basle, Switzerland 2 Department of Radiology, University Hospital Basle, Switzerland 3 Department of Orthopaedic and Trauma Surgery, Kantonsspital St. Gallen, Switzerland

Received: 25 May; accepted: 11 July 1995

Abstract . We assessed the patients who were operated on in a combined procedure from 1980 to 1992 with anterior cruciate ligament (ACL) insufficiency, cartilaginous le- sions of the medial compartment, lesion of medial menis- cus and varus malalignment. The combined operative pro- cedure was autologous intra-articular ACL reconstruction with the middle third of the patellar ligament - partially augmented with Kennedy-ligament augmentation device (LAD) in hot dog technique - and high tibial osteotomy. The patients were examined according to the criteria of IKDC including testing of anterior stability with the KT- 1000 arthrometer. Radiographically we checked axis and arthritis according to a modified score of Kannus. Twenty- seven of 34 patients who fulfilled the inclusion criteria could be followed up in three categories (2-5 years post- operatively, 5-10 years postoperatively, over 10 years post- operatively). Total qualification was good in 37%; there were no perioperative complications. Rehabilitation was not prolonged. Eighty-nine percent practised their preop- erative job, over 50% had a higher level of sports activi- ties than preoperatively, and more than 25% regained their pretraumatic sports capacity. Two-thirds had no giving way and less than 3 mm translation difference in compar- ison to the contralateral knee. Seventy-five percent of pa- tients would accept the operation again. Radiological findings had no correlation to overall qualification. The encouraging results with respect to many of the criteria suggest using the combined procedure in a young patient with ACL insufficiency, varus malalignment and medial compartment damage including medial meniscus lesion.

Key words: Anterior cruciate ligament - High tibial os- teotomy

Zusammenfassung . Im Sinne einer Qualitfitskontrolle wur- den die yon t 980 bis 1992 an der orthopaedisch-traumato-

No author or related institution has received any financial benefit from research in this study. See acknowledgement for funding in- formation. Correspondence to: A. P. Boss, Orthopaedische Universit~ttskli- nik, Felix-Platter-Spital, Burgfelderstrasse 101, CH-4012 Basel, Switzerland

logischen Abteilung des Kantonsspitals Basel einzeitig operierten Patienten bei vorderer Kreuzbandinsuffizienz, medialem Knorpelschaden, medialer Meniskuslaesion und Varusmorphotyp nachuntersucht. Es handelt sich um einen Kombinationseingriff von vorderer intraartikulaerer Kreuz- bandersatzplastik mit mittlerem Drittel des Ligamentum patellae - z.T. augmentiert mit einem LAD Band nach Ken- nedy in hot dog Technik - und Achsenkorrektur der pro- ximalen Tibia. Die Patienten wurden gem~iB Richtlinien des IKDC klinisch nachuntersucht und zus~itzlich appara- tiv die Stabilit~t mittels KT-1000-Arthrometer untersucht und radiologisch Achsen und Arthrose nach Kannus be- stimmt. Zusatzfragen wurden anhand eines Fragebogens beantwortet. 27 von 34 die EinschluBkriterien erffillenden Patienten (79%) konnten in 3 Kategorien (2-5 Jahre post- operativ, 5-10 J. postop und fiber 10 J. postop) nachunter- sucht werden. Die Gesamtqualifikation war gut bei 37%, peri- und frtihpostoperative Komplikationen fehlten, die Dauer der Rehabilitation war nicht verlfingert, 89% gingen dem praeoperativ ausgefibten Beruf nach, tiber die H~ilfte der Patienten konnte die sportliche Aktivit~t gegeniiber prae- operativ steigern und 1 u sogar die Sportaktivitfit vor dem Unfall wiedererlangen und die subjektive (2/3 ohne Giving way) und objektive Stabilit~t (2/3 bis 3 mm Trans- lationsdifferenz zur gesunden Seite) der operierten Knie- gelenke war gut. Drei Viertel der Patienten wiirden sich den Eingriff wieder durchftihren lassen. Die radiologi- schen Ergebnisse korrelieren nicht mit der Gesamtqualifi- kation. Die ermutigenden Nachkontrollergebnisse hinsicht- lich vieler kontrollierter Kriterien sprechen ftir das einzei- tige Verfahren beim jtingeren Patienten mit vorderer Insta- bilit~it, Varusmorphotyp und medialem Kompartimentsscha- den inklusive medialer Meniskuslaesion anstelle der Durch- ffihrung nut eines Eingriffs oder beider mit Intervall.

In troduc t ion

There are only a few studies in the literature concerning anterior cruciate ligament (ACL) reconstruction com- bined simultaneously with high tibial osteotomy (HTO) [9, 14, 17, 22, 25-28]. Often there are only a few patients -

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or even none [25] - or a short follow-up period. Prospec- tive studies are missing. Because of different examination criteria and operation techniques, they are not compara- ble. The operation is individually proposed in young sportive patients with anterior knee instability in combi- nation with beginning medial gonarthrosis or varus malalignment. Lesions of the medial meniscus are often found at preoperative or arthroscopy performed earlier. The aim of the operation is not complete sportive rehabil- itation but a stable knee without pain and delay of arthritic progression. A C L reconstruction is able to correct anterior instability, high tibial valgisation osteotomy reduces the load of the medial compartment. To achieve these aims, a combined technique is proposed which does not have too many complications. We fol lowed up our patients in a ho- mogenous collective since 1980 in a quality-control study.

Materials and methods

From 1980 to 1992 54 patients were operated on simultaneously for ACL-plasty and high tibial valgisation osteotomy. We ex- cluded patients with a pre-existing ligament reconstruction (13), with additional extra-articular stabilization (3), other intra-articular procedures except meniscus surgery or extra-articular ligament op- erations (7). Twenty-seven of 34 patients fulfilling the study crite- ria could be followed up, 7 could no longer be reached. Patients were examined according to the IKDC evaluation form [15], and additionally questioned by two doctors not involved in the opera- tion or treatment. Anterior stability was tested by KT-I000 arthrometer (MEDmetric Corporation, San Diego, Calif.) using manual maximum test in correlation to the contralateral knee [3, 6]. X-ray documentation included an antero-posterior X-ray on both legs, a tunnel X-ray and both patella in axial view. Addition- ally to IKDC criteria our radiologist performed an evaluation ac- cording to a slightly modified score by Kannus [20] instead of older scores [1, 12, 21]. Statistical investigations were done using the jmp-statistic program with the aid of Dr. P. Jordan from the University Calculation Center Basle.

Operations were performed by experienced surgeons. Preoper- atively patients were investigated by arthroscopy, most often am- bulatory under local anesthesia. Incision was parapatellar laterally. Primarily final valgisation osteotomy was performed (24 times with lateral closing, 3 times with medial opening) with subcapital fibular osteotomy and only 4 midshaft fibula osteotomies. Fixation was performed with staples, AO-T-plates or semitubular plate and long screw in the ventral tibial cortex. ACL-plasty modified ac- cording to Eriksson-Trillat was secondarily perfolwned using a me- dial and lateral arthrotomy or later through Hoffa fat pad with fix- ation of bone block through the lateral femoral condyle. Since 1987 a Kennedy-ligament augmentation device (LAD) in hot dog technique [13] was fixed over the top in 13 patients. After testing of isometry the distal bone plug was also fixed with screw or sta- ples. Postoperative treatment was performed with immediate pas- sive motion of the knee, and early mobilization of patient with a dorsal cast. Before dimissal from hospital a removable circular splint was applied with permission to full weight-bearing. Oral an- ticoagulation was given until full weight-bearing without a cast. The first clinical and radiological investigation was 6 weeks post- operatively. Physiotherapy was continued 2~4 times a week. At 3 months after the operation cycling and careful jogging were al- lowed, then 6-9 months postoperatively more demanding sports.

Results

There were 81.5% men. Patients' mean age at operation was 36 years (range 19-55) and at fol low-up 43 years

(range 26-68) . Interval f rom operation to fol low-up was 75 months (range 31-166); 6 patients (22%) were fol- lowed up 2 -5 y postoperatively, 14 (52%) for 5 -10 years and 7 (26%) for over 10 years. In 81.5% of patients the operation was done more than 2 months posttraumatically. Most causes of incident were sports (85%). The right side was dominant (67%). In 5 patients the contralateral knee was also affected. Twenty patients (74%) had a medial meniscus lesion of which 4 had undergone total medial meniscectomy. Medial meniscus procedures were pre- dominantly performed with preoperative ambulant ar- throscopy. All patients had arthroscopically verified me- dial cartilage lesions.

There were no intraoperative complications. Postoper- atively there were no infections, no haematomas demand- ing therapy, no thromboembolisms, no peroneal lesion, no compartment syndrome, no dystrophic signs and no pseudarthrosis. Two patients suffered a sensitivity distur- bance around the scar. Five patients underwent another arthroscopy because o f troubles and limited knee mobil- ity, two patients twice. One patient underwent closed knee mobilization, another one revarisation procedure and later arthrotomy for revision, another after almost 2 years me- dial opening wedge osteotomy.

With respect of subjective findings 89% had the same profession at follow-up as preoperatively. Also, 27% en- joyed the same sports activity as before trauma, and 52% had a higher sport activity than preoperatively but not than pretraumatically. Only 15% reduced sports activity because of their knee. Activity level was higher at follow- up in 55%, lower in 15% in relation to preoperatively. In all, 75% were satisfied with the result of operative treat- ment and would agree with it once again.

'Subjective f indings ' according to IKDC 'how is the function o f your knee ' resulted in a ' normal ' and 'a lmost normal ' result in about 80% and ' how does your knee in- fluence your activity ' resulted in a 'normal ' and 'a lmost normal ' qualification in 67%.

The qualification group 'Symptoms ' , which should de- tail the greatest activity without pain, swelling and giving way, had about 55% 'normal ' and 'a lmost normal ' , about 22% 'abnormal ' and about 26% 'very much abnormal ' qualification. Pain is mainly responsible for the unfavor- able results; swelling was seldom a problem. Two-thirds of the patients did not suffer giving way in knee-loading activities.

Clinical investigation showed no difference of exten- sion in 93% (up to 3 deg in correlation to contralateral knee) and in about 50% a flexion deficit of more than 16 deg com- pared with the contralateral knee, but without disturbance.

The Lachman test showed anterior dislocation up to 5 m m in 81.5%, and only 1 patient had more than 10 mm. Pivot shift was negative in 93%. Medial and lateral artic- ulation opening was up to 2 m m in 70%, and there was no opening more than 10 mm.

Total qualification results f rom the worst group quali- fication and had 26% 'very much abnormal ' , 37% 'abnor- mal ' , 34% 'a lmost normal ' and only one patient 'normal ' . A good overall qualification existed in 37%, and poor in 63%, whereas most of them are from the 5 -10 year post- operative fol low-up group (Figs. 1 and 2).

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14

12

10

8

6

4

2

0

[ ] >2 y postop [ ] >5 y postop [ ] >10y postop

IWIoDW I lb., to i i i i i i i i i i i i i t i

A1 B1 C1 D1 A2 B2 C2 D2 A3 B3 C3 D3 A4 B4 C4 D4 1. Subjective 2. Symptoms 3. Range of 4. Ligaments

motion

Fig. 1. IKDC group qualification (n = 27 patients)

lo ]

8

6.

4

2

Fig.2.

[ ] >2 y postep

Normal Nearly normal

IKDC total qualification (n =

~>; -1 .> ; '>>1-2 . ; - :

' 1 " : ' : ' ; ' : ' : ' 2 " : ' ; ' : ' : �9 . . . . . . . . . . . . . . . . . . .

iii/IIII/ Abnormal

27 patients)

Very abnormal

10-

8 . . . . . . . . .

6 ' " ' " ' " ' " ' " ' " ' " " . . . . . . . . . . . . . .% . . . . > ; . > : . ; . : . : . >> : . :

4 :::::::::::::::::::::: . . . . . . . . . . . . . . . . . . . .

2 - : : : : : : : : : : : : : : : : : : : : : :

iiiiii!iii!iiiiiii!i;ii Q . . . . . . . . . . I

0-2 mm

Fig.3. KT-1000 patients)

[ ] >2 y postop [ ] >5 y postop m _ d~ . . . . . , - _

~-~ mm >5 mm Injured opposite knee

arthrometer (difference to opposite knee; n = 27

12-

10-

8

6

each had crepitations in the medial and lateral compart- ment. Pain, irritation or sensibility problems of the trans- plant bed were numerous but without nuisance value. Functional test using one leg hop showed equal distance in about two-thirds. Maximum manual traction test using KT-1000 arthrometer under at minimum 130 N stress could be analysed in only 22 patients because of lesions of the contralateral knee in 5 patients. Two-thirds had an an- terior shift difference of up to 3 mm in correlation to the uninjured knee, and only 15% had a worse anterior stabil- ity than the corresponding knee. The greatest difference was 6 mm in only one patient (Fig. 3).

Radiological findings showed mainly femorotibial val- gus angles of 5-10 degrees. There were no varus angles. Angle difference from corresponding knee was 3-7 de- grees. Compartmental joint space was with few excep- tions over 2 mm. The investigation using the modified Kannus score with a maximum of 80 points showed no osteoarthrosis (> 74 points) in two cases~ mild os- teoarthrosis (69-73 points) in 4, moderate (64-68 points) in 9 patients and severe arthrosis (< 63 points) in 12. On average there were 62 points with qualification 'severe arthritis'. Corresponding knees showed no arthritis. In 20 patients there is a difference of 9.3 points (1-52) between the preoperative and control radiograph. The difference to the non-injured knee was 11.2 points; only one patient had a worse score in his non-injured knee (Fig. 4).

Statistical investigations did not show any significant difference between the three control groups according to age, sex and activity level during operation. Significant correlations only exist between pain and swelling (P = 0.001) and between total qualification and activity reduc- tion (P = 0.001) according to Spearman test. Group qual- ifications 'subjective findings' (P = 0.001) and 'symp- toms' (P = 0.001) correlated to total qualification in con- trast to 'mobility' and 'ligaments'. Manual maximum test has no correlation to subjective function, pain, swelling, giving way or radiological results. There is no correlation between modified Kannus evaluation and clinical findings or KT-1000 testing nor is there any correlation between Lachman test and arthrometer. Meniscectomy has no sta- tistical effect for arthritis, but there exists a mild correla- tion (P = 0.0276) to anterior stability tested by arthrome- ter in Wilcoxon test. There was no statistically significant difference in Wilcoxon test between the groups with LAD augmentation and no augmentation nor between their sta- bility.

4 -

2-

0- NO artnrosis Mild arthrosis Moderate Severe

arthrosis arthrosis

Fig.4. Osteoarthrosis according to Kannus of operated knee (n = 27 patients)

The following findings do not influence the IKDC to- tal qualification, but are interesting as well. Compartment findings were predominantly patellofemoral crepitations in one-third, but only painful in 4 patients. About 20%

Discussion

In a homogeneous patient collective we investigated the outcome of patients operated on simultaneously for ACL- ligament plasty and high tibial valgisation osteotomy. The aim of this procedure is not full rehabilitation of sports ac- tivities but reduction of medial compartment pain, a stable knee in daily life and resumption of light sports activities. According to Sherman et al. [29] anterior knee instability produces degenerative osteoarthrosis, which shows char- acteristic radiograph changes [20]. The extent of these signs depends on the degree of instability [ 11, 20]. In an

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untreated ACL rupture there were 84% meniscal lesions and 86% findings of osteoarthrosis [24]. Cartilaginous le- sions occur during ACL trauma in 23%, are present in 54% after 4 years [18] and are constant 10 years after trauma [10]. Meniscus lesions are often combined with anterior laxity and precede osteoarthrosis [22]. Anterior instability combined with a medial meniscal lesion aggra- vates osteoarthrosis [9]. The medial meniscus has a stabi- lizing function in preventing anterior translation [23]. An- terior knee instability causes osteoarthrosis in active sportsmen and may produce varus malalignment because of medial joint space narrowing or lateral decompensation [7]. Early reconstruction of anterior stability may prevent osteoarthrosis [19, 22], but according to Aubriot and Ri- vat [2] and Daniels [5] ACL reconstruction is not able to prevent osteoarthrosis. Arthritis is found more often after unsuccessful operative reconstruction of the ACL [9]. Ac- cording to Jakob [19], high tibial valgisation osteotomy is indicated in beginning characteristic degenerative changes in the medial compartment with varus morphotype, lateral instability and missing lateral osteoarthrosis. Dejour [8] recommends high tibial osteotomy in a knee with medial osteoarthrosis because of anterior instability and in the case of symptomatic subjective and objective instability also ACL reconstruction. Noyes et al. [27] does not pro- pose high tibial osteotomy in all varus knees with anterior instability, especially not in asymptomatic patients even when there is arthroscopic evidence of medial femorotib- ial arthritis because of the lack of long-term results and the complication rate of HTO. Should HTO be done alone? Can we avoid unnecessary ACL reconstructions using a two-stage procedure in reconstructing anterior sta- bility only in persisting instability? Lerat et al. [22] does not agree because of a lack of studies proving that HTO can prevent instability, because there is no progression of arthritis using a correct technique, and because there is no higher rate of complications or technical problems in a combined operation. He uses a combined technique in ad- vanced medial cartilage damage also. Our study supports this opinion; we did not have an elevated rate of compli- cations or technical problems. We did not see haema- tomas, infections, peroneal nerve lesions, compartment syndrome or pseudarthrosis. Reoperations were due to limited mobility and material removal and two angular corrections of osteotomy. Rehabilitation was not pro- longed or complicated; there was only one operation and one rehabilitation instead of two procedures with an inter- val - not all patients underwent metal removal. A com- bined operation is also considered a salvage procedure for a significantly disabled knee [26, 28] and is an operation for specialists. The patient has to understand beforehand that this operation cannot guarantee a highly active lifestyle in the long term [27]. Our results present an ac- ceptable long-term follow-up with no difference in the three groups concerning clinical and subjective results. Prospective studies should be performed to compare HTO alone, HTO combined with ACL reconstruction and ACL reconstruction alone in similar patients' collectives for a definitive proposal of procedure.

Our collective had a valgus angle predominantly from 5 to 10 deg, which is more than in other studies [10, 19]

but in accordance with Coventry et al. [4]. We could not see a disadvantage according to stability or lateral arthri- tis or activity score. A recommendation for overcorrecting exists also [25]. There was a high acceptance rate of the operation and patients' satisfaction was 75%, which is in contrast to the abnormal and very abnormal total qualifi- cation according to IKDC evaluation in more than 60%. Other protocols achieved better results. The IKDC evalu- ation protocol was not yet been validated [16] but has the advantage that it does not hide existing problems among arbitrary numbers. Worst group qualification is total qual- ification; unfortunately there are only four groups respon- sible for total qualification. Some relevant parameters are missing. The evaluation regime used gives a true standard also in relation to a non-injured and non-operated knee because we know from experience that most of the times only they have normal function. Objective stability results are good. Negative pivot shift in 93% may be explained by valgisation, which is supposed to reduce the shift rate without ACL reconstruction [27]. There does not exist a correlation of KT-1000 to subjective giving way or pain or swelling or subjective function of the knee. This test is only semi-objective [16] and a good result is not ab- solutely defined. IKDC total qualification correlates with postoperative activity reduction related to the pretrau- matic activity but not with subjective function. Of interest is also the unknown correlation of total qualification and KT-1000 manual maximum test to radiological os- teoarthrosis. A lack of correlations of the KT-1000 test with subjective function of knee, with Lachmann test, with pain, swelling and giving way put its use in question.

In conclusion, subjective and clinical results, a high satisfaction rate of most patients even in the long-term follow-up groups, lack of severe complications and preservation of profession and often sports activities are causes to discuss this combined procedure in young and active people with varus morphotype, medial cartilage and menisci lesions combined with acute or chronic ante- rior instability. There is no lengthening of the rehabilita- tion period or increase of morbidity. The operation should be done before there are too many degenerative changes because we cannot correct existing osteoarthritis but can stop its progression. Given the correct indication, the de- scribed procedure may be proposed in individual patients, without a higher risk than in a staged operation but with the advantage of only one rehabilitation period and inabil- ity to work.

Acknowledgements. We thank Dr. P. Jordan from University Cal- culation Center Basle for his support in statistics and SUVA assur- ance Lucerne and science fund of University Hospital Basle for fi- nancial support for radiographs.

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